The present invention generally relates to construction materials and, more particularly, to a mortarless wall block of an improved type.
Conventional concrete block walls are laid up by a time-consuming difficult procedure which involves troweling a layer of concrete mortar onto a level concrete or stone base or the like, or the top of a course of previously laid blocks and then setting blocks one at a time in the mortar layer, in each instance also applying mortar to the end walls of each block to join the blocks together. This procedure is continued until the required number of courses are laid. Great care must be taken to keep each course perfectly horizontal and straight. Few people have the skill to carry out such a procedure in a competent manner. Therefore, the cost of such construction is always high.
Various types of interlocking blocks have been devised in the past to facilitate block laying. However, most such blocks are very expensive to produce since the interlocking portions, usually grooves and protrusions, normally are sawed into or otherwise fashioned in the blocks after they are initially formed by molding. Moreover, those interlocking blocks in which the interlocking components are initially molded usually are very difficult to mold to acceptably close tolerances.
An improved interlocking mortarless building block overcoming these deficiencies is set forth in U.S. Pat. No. 3,888,060 issued June 10, 1975, to the inventor of the present invention. That block has been used successfully for a number of years. The block includes flat faced, spaced vertical sidewalls joined by flat faced vertical transverse webs to form a series of cells. The blocks are disposed one upon another in ascending courses in staggered relationship during the construction of a wall. The superposed block cells fully communicate with each other.
It has been found that under certain circumstances, additional structural strength is needed and that when wet concrete is poured into the cells and allowed to dry the poured concrete does not always fully adhere to the flat cell walls with maximum strength. Strength is in part due to the surface area of contact between the block walls and the set poured cement.
Accordingly, it would be desirable to be able to provide an improved mortarless building block featuring improved adaptability, strength and economy. The design of the block should be such that it can be readily moulded and released from the forming mold with full detail preserved, obviating any subsequent reshaping, finishing, etc. Moreover, the block should be easily strengthened with reinforcing bars, if needed, and be capable of being fabricated in a full array of sizes and shapes.